I've tried again, it keep to work fine for me.
Have you try to do same actions in IE browser ? does it work in your IE browser?
I have some proposals :
1) Please you make sure that you have a clear IE browser withou installing extra plugins.
2) Disable antivirus software / firewall.
3) Keep to update to latest version of IE browser.
4) Uninstalling VWR completely including the installation folder / files. then you re-install the latest version 3.0.6.
5) Trying to setup proxy in project , this will make sure that it's not a local network issue. we've provide a free private proxy switch for you.
Afterwards, if you still cannot go through the form submitting with AJAX dropdwon, please you attach your teamviewer ID & Passowrd in here, then I will log on your PC for diagnose further. (our working time is in 8am ~ 4pm in A.U.S GMT+8)